The art is relatively well defined relating to ridge cap roof ventilators fabricated from corrugated plastic sheet material and folded to form two vent parts disposed on opposing sides of an opening in a roof peak and an intermediate top panel.
U.S. Pat. No. 4,803,813 to Fiterman and U.S. Pat. Nos. 5,04,041 and 5,331,783 to Kasner describe various methods for scoring, folding, and routing blanks of corrugated plastic sheet material to form the roof vents, as well as their method of installation and use.
These folded roof ventilators and similar designs were traditionally made and sold in lengths of approximately four feet. However, a hinged double-length roof vent was developed as disclosed in U.S. Pat. No. 5,304,095 to Morris which enhanced the shipping and installation of such roof vents.
In comparison, other types of highly flexible roof covering products such as shingles, tar paper, and some roof ventilation products fabricated from open celled foam or other pliable materials are distributed in roll form, which permits longer lengths of product to be installed in one operation without transitions, and eliminates some potentially undesirable features such as seams or gaps.